Indoor climate for comfortable sleep, considering heat and moisture transfer between the room, bedding and human body : Optimal control of an air-conditioner

与醒着的时间相比，让房间保持舒适的睡眠时间是很困难的，因为在睡眠期间，室内气候不能根据人的热感觉来自动控制。如果建立了人体的热舒适性与睡眠时室内热状况之间的关系，就可以根据这种关系来调节房间的热环境，以满足睡眠时的热舒适性。然而，由于睡眠时不能报告热感觉，因此尚未确定睡眠时热感觉与人体与周围环境之间的生理反应或热传递之间的关系。因此，我们提出了一种热控制系统，该系统根据清醒时的热感觉指数反馈睡眠时热感觉的计算结果，并重新设置空调的目标温度。该系统预测睡眠时的热感指数。它可以反馈计算结果，以重新设定空调的目标温度。在本研究中，利用一名年轻受试者在夏季和冬季进行了睡眠实验，初步假设在该系统下睡眠时有一个舒适的热感觉区域。结合热感觉指数预测值对目标温度进行了较好的控制，并随时间收敛到舒适区。热感觉预测值的稳定时间分布与睡眠时不醒来，从而获得舒适的睡眠密切相关。因此，所提出的预测热感觉指数的空气控制系统可以有效地创造舒适的室内睡眠环境。

It is difficult to keep a room comfortable for sleeping compared to waking hours, because the indoor climate cannot be voluntarily controlled according to one's heat sensations, during sleep. If a relationship between thermal comfort for the human body and indoor thermal condition while sleeping is established, thermal environment of the room could be regulated according to the relationship to satisfy thermal comfort during sleep. Since thermal sensation cannot be reported while sleeping, however, relationships between thermal sensation and physiological responses or heat transfer between the human body and ambient environment during sleeping haven't been determined yet.Therefore, we proposed a thermal control system, which feeds back the calculated result of thermal sensation during sleep based on a thermal sensation index while awake and resets the target temperature of an air conditioner.In this study, an air control system providing an indoor thermal environment for comfortable sleep is proposed. This system predicts an index for thermal sensation while sleeping. It can feed back the calculated results to reset the target temperature of an air conditioner. In the present study, sleep experiments were carried out during both summer and winter seasons using a young subject by tentatively assuming a comfortable zone of thermal sensation during sleep under this system. The target temperature was well controlled in conjunction with the predicted value of the thermal sensation index, which converged into the comfortable zone with time. A stable time profile of the predicted values for thermal sensation is closely related to no awakening while sleeping and thus a comfortable sleep. Therefore, the proposed air control system that predicts the thermal sensation index could be effective in creating a comfortable indoor climate for sleep.